X0306 4 2020-12-07 0 0001351288 GW PHARMACEUTICALS PLC GWPH 0001754125 Snyder Douglas B. SOVEREIGN HOUSE, VISION PARK, HISTON CAMBRIDGE X0 CB24 9BZ UNITED KINGDOM 0 1 0 0 Chief Legal Officer Ordinary Shares 2020-12-07 4 S 0 4800 10.84 D 22104 D Ordinary Shares 2020-12-07 4 S 0 9444 10.95 D 23660 D Ordinary Shares 2020-12-07 4 S 0 3984 11.02 D 8676 D Ordinary Shares 2020-12-07 4 S 0 5076 11.11 D 3600 D Ordinary Shares 2020-12-07 4 S 0 1200 11.19 D 2400 D Ordinary Shares 2020-12-07 4 S 0 2400 11.30 D 0 D The sale reported was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 6, 2020. Following the exercise, these shares were converted into American Depositary Shares ("ADS") of the Issuer. Each ADS represents twelve ordinary shares of the Issuer. Converted from price per ADS. The price reported in Column 4 is a weighted average price per ordinary share ($130.0325 per ADS). These shares were sold in multiple transactions at prices ranging from $129.69 per ADS (or $10.81 per ordinary share) to $130.50 per ADS (or $10.88 per ordinary share), inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range. Converted from price per ADS. The price reported in Column 4 is a weighted average price per ordinary share ($131.3749 per ADS). These shares were sold in multiple transactions at prices ranging from $130.83 per ADS (or $10.90 per ordinary share) to $131.81 per ADS (or $10.98 per ordinary share), inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range. Converted from price per ADS. The price reported in Column 4 is a weighted average price per ordinary share ($132.2066 per ADS). These shares were sold in multiple transactions at prices ranging from $131.87 per ADS (or $10.99 per ordinary share) to $132.30 per ADS (or $11.03 per ordinary share), inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range. Converted from price per ADS. The price reported in Column 4 is a weighted average price per ordinary share ($133.2948 per ADS). These shares were sold in multiple transactions at prices ranging from $132.90 per ADS (or $11.08 per ordinary share) to $133.64 per ADS (or $11.14 per ordinary share), inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range. Converted from price per ADS. The price reported in Column 4 is a weighted average price per ordinary share ($134.3200 per ADS). These shares were sold in multiple transactions at prices ranging from $134.32 per ADS (or $11.19 per ordinary share) to $134.32 per ADS (or $11.19 per ordinary share), inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range. Converted from price per ADS. The price reported in Column 4 is a weighted average price per ordinary share ($135.6500 per ADS). These shares were sold in multiple transactions at prices ranging from $135.65 per ADS (or $11.30 per ordinary share) to $135.65 per ADS (or $11.30 per ordinary share), inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range. /s/ Douglas B. Snyder 2020-12-09